Evidence for the involvement of lung-specificy gamma delta T cell subsets in local responses to Streptococcus pneumoniae infection

TY - JOUR

T1 - Evidence for the involvement of lung-specificy gamma delta T cell subsets in local responses to Streptococcus pneumoniae infection

AU - Kirby, Alun C.

AU - Newton, Darren J.

AU - Carding, Simon R.

AU - Kaye, Paul M.

PY - 2007/12

Y1 - 2007/12

N2 - Although 76 T cells are involved in the response to many pathogens, the dynamics and heterogeneity of the local 76 T cell response remains poorly defined. We recently identified gamma delta T cells as regulators of macrophages and dendritic cells during the resolution of Streptococcus pneumoniae-mediated lung inflammation. Here, using PCR, spectratype analysis and flow cytometry, we show that multiple 75 T cell subsets, including those bearing V gamma 1, V gamma 4 and V gamma 6 TCR, increase in number in the lungs of infected mice, but not in associated lymphoid tissue. These 76 T cells displayed signs of activation, as defined by CD69 and CD25 expression. In vivo BrdU incorporation suggested that local expansion, rather than recruitment, was the principal mechanism underlying this increase in gamma delta T cells. This conclusion was supported by the finding that pulmonary 78 T cells, but not alpha beta T cells, isolated from mice that had resolved infection exhibited lung-homing capacity in both naive and infected recipients. Together, these data provide novel insights into the origins of the heterogeneous gamma delta T cell response that accompanies lung infection, and the first evidence that inflammation-associated 76 T cells may exhibit distinct tissue-homing potential.

AB - Although 76 T cells are involved in the response to many pathogens, the dynamics and heterogeneity of the local 76 T cell response remains poorly defined. We recently identified gamma delta T cells as regulators of macrophages and dendritic cells during the resolution of Streptococcus pneumoniae-mediated lung inflammation. Here, using PCR, spectratype analysis and flow cytometry, we show that multiple 75 T cell subsets, including those bearing V gamma 1, V gamma 4 and V gamma 6 TCR, increase in number in the lungs of infected mice, but not in associated lymphoid tissue. These 76 T cells displayed signs of activation, as defined by CD69 and CD25 expression. In vivo BrdU incorporation suggested that local expansion, rather than recruitment, was the principal mechanism underlying this increase in gamma delta T cells. This conclusion was supported by the finding that pulmonary 78 T cells, but not alpha beta T cells, isolated from mice that had resolved infection exhibited lung-homing capacity in both naive and infected recipients. Together, these data provide novel insights into the origins of the heterogeneous gamma delta T cell response that accompanies lung infection, and the first evidence that inflammation-associated 76 T cells may exhibit distinct tissue-homing potential.

KW - cell homing

KW - gamma delta T cells

KW - lung inflammation

KW - mucosal immunity

KW - ESCHERICHIA-COLI INFECTION

KW - PULMONARY DENDRITIC CELLS

KW - ALVEOLAR MACROPHAGES

KW - INFLUENZA PNEUMONIA

KW - MURINE INFLUENZA

KW - MICE

KW - LYMPHOCYTES

KW - EXPRESSION

KW - INFLAMMATION

KW - ACTIVATION

U2 - 10.1002/eji.200737216

DO - 10.1002/eji.200737216

M3 - Article

C2 - 18022862

SN - 0014-2980

VL - 37

SP - 3404

EP - 3413

JO - European Journal of Immunology

JF - European Journal of Immunology

IS - 12

ER -